distributor vacuum advance hook up

[Nick W]

Good day,

I have taken on a project wrangler that has a 258 block with the 4.0 head and efi. Not to rare I know. But my question is, Were is the optimal place for the vacuum line from the actuator on the distributor? Currently the line goes from the actuator to the nipple on the intake. I have had the chance to look at the 4.0 valve cover set up on a TJ and the line from the valve cover goes to back of the intake manifold, which is how mine is.

Part two: I understand that there are far superior distributor set ups available and that will come, any recomendations?

Thanks for looking

Nick

[Jeep-Power]

Nick-- the OEM (OBD1 & OBDII) 4.0 EFI setups, as far as I know, do not have vacuum advance. Is yours a Renix setup?

Whichever you have, I'm sure any port on the manifold will work well.

[Nick W]

Thanks for the reply. The enitre intake manifold is from cherokee HO with the 7120 head. I see that the newer vehicles do not use a vacuum advance. I have read that the 4.0 distributor and the 4.2 are a direct swap. Might be the direction to go in. At this time could I simply plug the vacuum advance, and would this require me to retime the ignition?

On a side note I have read that the vacuum advance should not be connected to manifold vacuum.

Thanks

Nick

[Nick W]

jeep-power

Just realized that we seem to have very similar set ups, are you using the factory efi ecu?

Nick

[Jeep-Power]

if you have a vacuum advance dist, they certainly hook it up to vacuum. they will not advance spark properly with it disconnected.

jeep-power

Just realized that we seem to have very similar set ups, are you using the factory efi ecu?

Nick

yes.


I'm sure you saw this thread

[Nick W]

Jeep-power, thanks for the info. Sounds like it might be worth swapping to a non vacuum advance distributor. Anything else needed to be done with swapping?

Thanks for your help

Nick

[Jeep-Power]

Anything else needed to be done with swapping?

i don't think so.

Just to confirm, you are already running the Mopar OBD1 EFI?

[Nick W]

acutally I am using a megasquirt ecu to control the fueling of the vehicle.

[Jeep-Power]

acutally I am using a megasquirt ecu to control the fueling of the vehicle.

OK-- that makes sense! I couldn't figure out how you were running the OBDI system without the OBD1 distributor...